Volts dropped after new amp install?
06-02-2009, 09:44 PM
#1
Volts dropped after new amp install? Hey guys,
I have two amps in my car, a 400W 4channel for the main speakers, and I used to have a piece of crap 425W that only put out 100WRMS for a sub. I replaced it today with an alpine 500W which is currently running at 300W @ 4OHM.
After I installed the amp, I was driving around, and noticed that my volts gauge was showing around 11V .. while the car was running obviously. Could this be bad? I didn't have any problems with anything though.
Yes, I have an underdrive pulley.
I have two amps in my car, a 400W 4channel for the main speakers, and I used to have a piece of crap 425W that only put out 100WRMS for a sub. I replaced it today with an alpine 500W which is currently running at 300W @ 4OHM.
After I installed the amp, I was driving around, and noticed that my volts gauge was showing around 11V .. while the car was running obviously. Could this be bad? I didn't have any problems with anything though.
Yes, I have an underdrive pulley.
06-02-2009, 10:45 PM
#3
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a capacitor WILL NOT help with the alternator being overloaded, and they are a waste of money, do a search. The first thing you could do is get an overdrive alternator pulley or if you have hptuners or efilive then you could bump the idle up by 100RPMs which worked for me.
06-02-2009, 11:53 PM
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was the music on full tilt or somthing? The voltage shouldnt drop when your just driving around and the amps are on but music isnt loud. even with my system thumping the volts never dip below 13.
06-02-2009, 11:57 PM
#6
Nope it was on at an average volume. I turned the whole stereo off and the needle went up a little. But not past 13. I've only noticed this today after I installed the amp. My alternator was checked a month or two ago and it was fine.
06-03-2009, 10:21 AM
#7
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so your needle is hitting 11V while you are driving or at idle? If it is dropping that low while you are driving then it is definitely a problem, especially if you are at an average volume. Check to see if you have the same problem with the volume at 0. When you turn the stereo off it probably also turns the amps off so that will rule out any wiring problems but if you see the same voltage drop at 0 volume then there is probably something wrong with one of your amps.
From personal experience, with my 480W subwoofer amp and 224W 2 channel amp with the idle bumped 100RPMs to 650RPMs, I could be sitting at a light, with the stereo up to a high volume, cooling fans running and the voltage only drops a bit. And this is an A4 with an underdrive crank pulley and stock alternator pulley. Once I get on the gas the voltage instantly increases to isn't normal reading.
From personal experience, with my 480W subwoofer amp and 224W 2 channel amp with the idle bumped 100RPMs to 650RPMs, I could be sitting at a light, with the stereo up to a high volume, cooling fans running and the voltage only drops a bit. And this is an A4 with an underdrive crank pulley and stock alternator pulley. Once I get on the gas the voltage instantly increases to isn't normal reading.
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06-03-2009, 01:16 PM
#10
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If he is seeing 11V while driving (2000+RPMs) then there is definitely something wrong that "the big 3" probably won't fix, especially if he is getting that voltage drop at even average volume (which will not run anywhere near the peak wattage per amp)
06-03-2009, 03:01 PM
#11
What's the big 3? I'll do a search in a bit..
Next time I take the car out I'll check while the car is moving. When I had noticed it, I was in drive with my foot on the brake waiting to pull out of the gas station. Unfortunately it's raining.. Thanks for all the help so far guys
Next time I take the car out I'll check while the car is moving. When I had noticed it, I was in drive with my foot on the brake waiting to pull out of the gas station. Unfortunately it's raining.. Thanks for all the help so far guys
06-03-2009, 03:19 PM
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big three is upgrading the 1. battery(+) to alternator 2. battery(-) to chassis 3. engine block to chassis. Usually people use 1/0 guage for all three but you can get away with a little smaller. Google it and you can see all kinds of big 3 installs. Vjo, it does help with the voltages, there may be another problem hes having but doing the big 3 will certainly help.
06-03-2009, 03:53 PM
#14
What's the big 3? I'll do a search in a bit..
Next time I take the car out I'll check while the car is moving. When I had noticed it, I was in drive with my foot on the brake waiting to pull out of the gas station. Unfortunately it's raining.. Thanks for all the help so far guys
Next time I take the car out I'll check while the car is moving. When I had noticed it, I was in drive with my foot on the brake waiting to pull out of the gas station. Unfortunately it's raining.. Thanks for all the help so far guys
https://ls1tech.com/forums/stereo-el...lternator.html
or my big 3
https://ls1tech.com/forums/stereo-el...rades-d-6.html
06-03-2009, 04:01 PM
#15
agreed some of these fbodys are 15 years old and OEM grounds are starting to fail and corrode apart. regardless do the big3 then if u still ahve problems start looking at other stuff. and the oem guage isnt the best judge either of voltage
